First step towards the development of tiny devices that produce electricity while performing everyday tasks is new approach. Imagine that you charge your cell phone while walking, thanks to the power generator thin like paper embedded in your shoe. This futuristic scenario is now a little closer to reality. Scientists from Lawrence Berkeley National Laboratory (Berkeley Lab), developed a way to produce electricity using harmless viruses that convert mechanical energy into electrical energy.
Researchers tested their methodology of creating a generator that produces enough electricity to run small liquid-crystal displays. It activates by touching the electrode size of a postage stamp. The electrode is coated with a layer of the viruses created specifically for this purpose. Viruses convert force of the touch into the electrical discharge.
Piezoelectricity
This is the first power generator that uses piezoelectric properties of biological materials. Piezoelectricity is the accumulation of charge in a solid material as a response to mechanical stress.
This process can lead to the production of small devices that generate electrical energy from the vibrations that occur when performing everyday tasks such as closing doors or climbing stairs. It also indicates the way to make microelectronic devices more easily. This is possible because the viruses organize themselves in a film that allows the operation of this generator. This is great advantage of manipulation with viruses.
"Further research is needed, but our work is a promising first step towards the development of personal generators for electricity, starters for use in nano-devices and other devices based on viral electronics," said Seung-Wuk Lee, a scientist at Lawrence Berkeley National Laboratory and an associate professor of bioengineering at the University of California, Berkeley. He conducted the study with a team that included Ramamoorthy Ramesh and Lee Byung Yang.
The piezoelectric effect was discovered in the 1880th and since then, it was observed in crystals, ceramics, costumes, proteins and DNA. It is also used a lot in practice. Electric igniters and microscopic scanners could not exist without it, just to mention a few of its applications. However, the materials used for making piezoelectric devices are highly toxic and difficult to work with, which limits the widespread use of this technology.
Bacteriophage M13
Lee and his colleagues wondered whether the virus is being studied in laboratories around the world to offer a better way of solving these problems. Bacteriophage M13 attacks only bacteria, while it is harmless to humans. Since it is a virus, it replicates itself in millions of copies in a few hours, so there is always a constant amount of virus available. It is also very easy to genetically modify the virus. In addition, a large number of such viruses naturally orient themselves in a beautifully decorated films.
These are the properties that scientists are looking for in order to make basic unit in nano technology. However, the researchers first had to determine whether the virus M13 is piezoelectric. Lee and Ramesh, who is an expert in the study of electrical properties of thin films in nano technology, applied the electric field to the film of the virus M13 and watched using special microscope what was happening. Helical proteins that cover viruses were inverted and opened in response to an electric field, which is a sure sign of the piezoelectric effect in action.
Furthermore, scientists have increased the piezoelectric effect of the virus. They have added to viruses four negatively charged amino acid residues at one end of the coil proteins that cover the virus. These residues increased the charge difference between the positive and the negative end of the protein, and that raised the voltage of the virus.
Scientists have further enhanced the system of film composition made of individual layers of the virus. They found that the film composed of 20 single layers showed the strongest piezoelectric effect.
The First Generator
What had left was to make a test. Therefore, scientists have created a piezoelectric power generator based on the virus. Such conditions are created for genetically modified viruses to be spontaneously organized in those multi-layered films that had the size one square centimeter. After that, the film is placed between two golden electrodes that are wired to a liquid crystal display. When pressed on the generator, the electricity of 6 nA and 400 millivolts is produced. That's enough electricity to turn up the number "1" on the screen.
"Now we are working on improvement the results of this demonstration which was supposed to show the correctness of our way of thinking," says Lee. "Because the tools of biotechnology allow mass production of genetically modified viruses, piezoelectric materials based on viruses could offer a simple way to develop new microelectronic devices in the future."
Researchers tested their methodology of creating a generator that produces enough electricity to run small liquid-crystal displays. It activates by touching the electrode size of a postage stamp. The electrode is coated with a layer of the viruses created specifically for this purpose. Viruses convert force of the touch into the electrical discharge.
Piezoelectricity
This is the first power generator that uses piezoelectric properties of biological materials. Piezoelectricity is the accumulation of charge in a solid material as a response to mechanical stress.
This process can lead to the production of small devices that generate electrical energy from the vibrations that occur when performing everyday tasks such as closing doors or climbing stairs. It also indicates the way to make microelectronic devices more easily. This is possible because the viruses organize themselves in a film that allows the operation of this generator. This is great advantage of manipulation with viruses.
"Further research is needed, but our work is a promising first step towards the development of personal generators for electricity, starters for use in nano-devices and other devices based on viral electronics," said Seung-Wuk Lee, a scientist at Lawrence Berkeley National Laboratory and an associate professor of bioengineering at the University of California, Berkeley. He conducted the study with a team that included Ramamoorthy Ramesh and Lee Byung Yang.
The piezoelectric effect was discovered in the 1880th and since then, it was observed in crystals, ceramics, costumes, proteins and DNA. It is also used a lot in practice. Electric igniters and microscopic scanners could not exist without it, just to mention a few of its applications. However, the materials used for making piezoelectric devices are highly toxic and difficult to work with, which limits the widespread use of this technology.
Bacteriophage M13
Lee and his colleagues wondered whether the virus is being studied in laboratories around the world to offer a better way of solving these problems. Bacteriophage M13 attacks only bacteria, while it is harmless to humans. Since it is a virus, it replicates itself in millions of copies in a few hours, so there is always a constant amount of virus available. It is also very easy to genetically modify the virus. In addition, a large number of such viruses naturally orient themselves in a beautifully decorated films.
These are the properties that scientists are looking for in order to make basic unit in nano technology. However, the researchers first had to determine whether the virus M13 is piezoelectric. Lee and Ramesh, who is an expert in the study of electrical properties of thin films in nano technology, applied the electric field to the film of the virus M13 and watched using special microscope what was happening. Helical proteins that cover viruses were inverted and opened in response to an electric field, which is a sure sign of the piezoelectric effect in action.
Furthermore, scientists have increased the piezoelectric effect of the virus. They have added to viruses four negatively charged amino acid residues at one end of the coil proteins that cover the virus. These residues increased the charge difference between the positive and the negative end of the protein, and that raised the voltage of the virus.
Scientists have further enhanced the system of film composition made of individual layers of the virus. They found that the film composed of 20 single layers showed the strongest piezoelectric effect.
The First Generator
What had left was to make a test. Therefore, scientists have created a piezoelectric power generator based on the virus. Such conditions are created for genetically modified viruses to be spontaneously organized in those multi-layered films that had the size one square centimeter. After that, the film is placed between two golden electrodes that are wired to a liquid crystal display. When pressed on the generator, the electricity of 6 nA and 400 millivolts is produced. That's enough electricity to turn up the number "1" on the screen.
"Now we are working on improvement the results of this demonstration which was supposed to show the correctness of our way of thinking," says Lee. "Because the tools of biotechnology allow mass production of genetically modified viruses, piezoelectric materials based on viruses could offer a simple way to develop new microelectronic devices in the future."
